Description:On a farm on the outskirts of Bogota, a team of researchers are digging a grave site. It's part of an experiment aimed at providing new techniques to locate tens of thousands of missing people in Colombia, most of whom are presumed dead due to a decades long internal conflict between the government and rebel forces. In these graves the scientists are burying human skeletons as well as pig cadavers, which they say decompose in much the same way as human bodies do.(2:58)